Actually that's quite a realistic goal you could set for yourself and work towards it. That could also help define you some of the features your game will need, as you're going to work for a more or less set audience. Also I think Steam Greenlight should have some standards you can stick to as guidelines (not sure, but I guess they have to have something like that).

I did not click on the links, so I have no idea how great they look or play or if they are even free or not. However I do enjoy castle engine/siege games and Newgrounds has plenty of free ones. Some are survive the waves while others are more knock down a slew of castles that go from hardly a few boards to actual castle walls and try to kill all the enemy soldiers. I suppose kind of like Angry Birds before there was such a game. But the problem with some of these games is that it becomes more of a puzzle than actual just trying to destroy stuff, since you only have so many rocks, or cannon shot, etc. and you have to use the right munition for the task and have just the right angle of the cannon and worry about the wind and then hope there is a domino effect. That becomes annoying quickly for me.

Not free! Not much on steam is; but I guess a few free-to-play games show up. I understand not clicking random links, but do you YouTube or Google image search? Or even straight to steam? That could give safe looks at any game, searching for the name or link. Or if it's another reason, no worries, just curious.

And I know what you mean by that puzzle-style problem - after the novelty of the framing and graphics wears off, the puzzles really start becoming the same in most of those games. It's either angry birds, or Tetris, or sokoban, or Chip's Challenge, rarely something new and different, especially in free games.

I don't think these are that type of puzzle game, though, more Lego building style simulation games with explosions! Someone said they tried to build a ballista or something, but it broke apart on first firing - but pieces flew back into the "builder's hut" and blew it up. Not success, but great fun!

To this day, Rampart is still my personal favorite and most frustrating castle building/sieging game and it is a couple of decades old I imagine by now. The arcade version used a track back. Sinking the ships were hard, but satisfying and trying to rebuild your castle was a real pain, because the blocks available were not chosen, but giving randomly. I am reading now from the wiki that it was easier to place your walls around another castle entirely than your own to capture it, but then you did not have cannons or something like that in that new castle, at least for a while. I never knew that. I always tried to fix my own castle. I always seemed to get a too long straight piece when I wanted a curve or one or two curved pieces when I wanted a straight. And when when I needed a third curved piece to complete that wall snuggly, I get a long straight piece and is just frustrating. And I did not realize it was multiplayer, I always just played on my own.

I just normally do not like clicking on links as a general rule of thumb. Plus as you said it was not free. I know a lot of people did not like Steam when it first appeared. I had it when it first came out, when they went from the normal servers (VAC was it?) to Steam. I did not really see a problem myself. I assume it was an attempt to stop cheating and or piracy or make servers work smoother, although I think being forced to run Steam made it harder for older computers. Plus a way to get potential sells for things.

And I thought there were a few games that were free or maybe only for a short while and or sold rather cheaply, like $3 or $4. Plus there are all those free player made mods, some of which are better than expensive store bought games or at least that was the general rule back in the Counter Strike/Day of Defeat/Natural Selection/Pirates, Vikings and Knights/Sven Co-op/Brain Bread days. I am not sure about now, but I am sure the mod makers are still making the games at least as good looking as possible, but more importantly making the games they want and trying new things others want. Meaning they are doing things their way, not the way of the publishers or being forced to a time limit of when it is finished.

Rampart! I loved that game, trackball glory. That's one I've spent some time with on Mame, and even setup a good large trackball to play at one point. It's been years though - that's a fun memory.

Steam: Yes, could be, I was a late adopter so don't recall much that I heard about the earlier days. But they and Gog.com won, so happy to be on both of them now. Their sales - entice me to add more games I don't have time to play to my stack of shame, for only a few dollars "we promise"!

I have never bought a Steam game unless HL2 counts, but I bought it on disks anyway, although again I stopped playing a little over a year after Steam came out. But I doubt I would buy anyway. I prefer the free games, not just because they are free, but as I said before, because of their fun factor and uniqueness.